Interested in the next BLF/Manafont custom light?

There is nothing to help the light escape in front which is ordinarily collected by a traditional reflector. Tir optic don't go along with reflectors (usually).

I have a feeling were confusing TIR with Aspherics

TIR is usually in the 90-96% efficiency range (similar to reflectors), while aspherics are in the 30-70% range of efficiency.

a TIR = total internal reflection lens is one that looks like a cone shaped solid plastic with a flat front, imagine if there was to be a piece of plastic that filled the volume within a reflector. The light travels within this plastic, and reflects off the plastic/air interface as if it was a reflector. These lenses usually sit over the emitter and are able to capture most (95%+) of the light from the emitter. They usually produce a well defined wide spot of light. Imagine a narrow spill light but with constant mid level brightness across the whole area.

An aspheric lens is one like those in magnifying glasses, a convex lens which only converges the light that goes Through it. It has high losses because it needs to be placed away from the emitter to focus, and is not in close association with the emitter. A large amount of light that is emitted from the LED sideways does not go to the lens (about half in a compact aspheric torch), and is therefore lost as energy heating up the torch instead. However aspheric lenses can be focused to make a very tight spot (image of the die) with no spill light. Flood to throw torches use aspheric optics. The flood option comes from bringing the lens out of focus.

Reflectors are common, and give a good mixture of throw (central hotspot) and flood for general mixed use with high efficiency 95%

TIRs make great general purpose flood lights and work lights for close range work requiring very smooth beam patterns, also high efficiency 95%

Aspherics are Great throw lenses, however can be very inefficient (50%). They can be improved by having very big lenses, or complicated optical systems that increase the capture of light, however there are diminishing returns, and efficiency is difficult to obtain economically.

Okwchin,

That was a fantastic explanation...you beat me to it!

i find this to be opposite of true.

the TIR optics i have are POORLY designed, and being such that they are clear on the sides, what you are missing is alot of light that they CLAIM is collected, yet ends up INSIDE the flashlight

a reflector however doesnt allow that lost spill and throws it out the front, in a direction you can at least use it

any optic, clear on the sides, means light will PASS THROUGH THE SIDE. this equals LOST light. if you dont believe me, take your LED and TIR out of the flashlight, set it on the table and see how much light ends up on the desk, a decent amount. i have yet to see a chinese TIR (or quality ones like LED lenser) give 95% efficiency. while guestimating, i would say more like 70%

but much better than any other LENS of course. not better than a reflector.

Would be nice to see it in practice: same light with different type of lenses and with reflector.

Just curious: from past experience - how long does it take for such a custom light to reach production?

Are we talking weeks? Months?

Should I buy another light meanwhile? ;)

Interesting numbers! I havent as yet got the gear to measure the actual performance of my TIRs, and yes, we do see light going out the back of the reflector. I think thats due to random reflections from the parts of the TIR that arn't exactly meant to be part of the reflective optical system. (mounting tabs, rounded moulding edges, moulding sprues, etc..

The theory behind TIR relies on the interface between the optical plastic and the air. For a given difference in refractive index, if light hits the interface at a low enough angle, it will be totally reflected back into the material (thus the name Total Internal Reflection). This is how fiber optic cables work (in simple terms). In a TIR, the angle of incidence between the light from the emitter and the sides of the TIR are supposed to be within this angle that allows internal reflection, and therefore losses are only from the losses through the material (giving 98% efficacy or something) however there are factors that can cause light to be lost, again related to quality and design.

1) Optic is too small compared to the emitting source (small optics, big leds) - results in a decrease in the ability for the optic to focus the light in the case of a reflector, but in a TIR, can actually cause light to be lost out the back because the light begins to go past the angle of incidence required for total internal reflection (less is reflected, more is refracted (out the sides)). I havent explained this too well, but its because the LED is wider, relative to the reflector, so the outer edges of the LED emit light which to the reflector are outside of its ideal focal point. Ray diagrams here would help.

Just thought of an example, looking into a fish tank, you can see through the far side of a fish tank if you look straight into the tank at right angles to the far side, however if you start looking through it at an angle to the far side, you will start to notice that the far side will start to look shiny and you cant really see out of the tank. Thats light that your seeing from somewhere else that has been reflected of the inside surfaces of the tank.

2) Optical quality of interface - TIR relies in the interface between the optical material and the outside air. Any contaminants, oil, fingerprints, scratches!!, dust will alter the ability for light to be internally reflected, and will result in losses

3) Moulding quality/Design - Many optics simply have rings at the outer edge to facilitate mounting the optic, however these become involved with light from the emitter, but the non ideal shape means light gets reflected around randomly. This may account for another 2-5% of light, which you will see as rings outside of the normal light output (out the front, sides, back, anywhere)

4) Design - TIRs Should be coupled with the intended emitter (as reflectors are) because they Should have been designed to accomodate the emissive characteristics of particular emitters. Many chinese lights save money by using generic TIRs, which for us means TIRs for luxeons (or their cheaper alternatives) for newer emitters such as crees. These don't work as well because they are difficult to focus accurately, without more complicated mounting systems, and are likely to induce more losses again.

Overall there are many places where light can be lost, but the story is not to different for any optical system. Cut the budget enough and there will be losses in performance. Reflectors are also high efficiency in theory, but the reflectivity of the surface, dust contamination, shape of the reflector, all these apply all the same.

Wow, what a good explanation :O Thanks for the info, guys ;)

TIR's basically work the same way prisms work, I'm sure you've all seen lasers being shot into them and it being completley (more or less) diflected.

So what you have with a TIR is an LED surounded by a circular prism, so it should give a very high transmitance percentage.

...but the TIR's we generally have cost almost nothing, so quality is presumably questionable.

I mostly don't like the TIR idea due to them almost always being plastic.

Plastic lenses are far easier to make accurately, in those complex shapes, than it is to make one out of glass. Slightly higher losses from lower transmittance, but gains from better quality finish and shape for the same effort/money.

Quoting earlier, the fact that the optic is transparent, does not mean it cant reflect light. The theory behind TIR is that most of the light is reflected, with some loss as explained before. The difference maybe compounded by perception - losses in a TIR are visible as light escaping, however in a reflector, light is just absorbed and converted to heat directly, we never see the lost light. Again, I don't have numbers, but subjectively speaking, it surely does feel that TIRs are less efficient...

  1. Maximum reasonable price - 25USD
  2. LED type : XPG-R4 neutral or XM-L (prefered)
  3. Mode arrangement : Hi / Med (30%) / Lo (3%) or even better. ramping like the UF-h2 (very low low)
  4. Mode memory? : yes
  5. NiMH and 14500 support : both, with +1A on 14500 (high) and 2A on Nimh
  6. neutral
    very fast pwm!!!

I'd like the design and the Vaio tint of the Farka E09

well either way, i took two flashlights, same emitter (q5) and compared their outputs.

same drivers, same 18650 batteries (trustfires that both tested capable of producing over 3 amps) but different optics

one with a TIR and one with a reflector (had both OP and SMO)

the TIR had the BEST quality beam, but it wasnt as wide, and clearly not as bright

the OP had close to the quality, and much more light

the SMO had the MOST light, but as its a q5, was VERY ringy.

so now your saying, how do you know its the same? i swapped out the TIR and reflectors to the opposite flashlights to get the SAME results.

now i dont have a measuring tool, but when you have 2 side by side, you can tell which one has more usuable light.

the TIR i had (which was designed for a cree XR-E) just did not cut it. so i ended up selling that flashlight to a friend who was in love with it lol

i have only two TIR flashlights at the moment, the BLF Mr. Lite and an LED lenser awaiting me to upgrade it.

the BLF Mr.lite is a great flashlight, but again, compared to my Aurora V6 Q5, has a bit less light overall.

however tough to compare those as they are COMPLETELY different power sources and drivers (14500 vs 18650, multimode vs single mode)

and the BLF is an XR-E R2, not an XR-E Q5 (which is all heresay due to poor quality control from china)

we already have a TIR optic flashlight that uses a 14500/AA

time to either go bigger, or smaller

go AAA or go 18650, or even cr123!

if you go AAA or single CR123 - XPG-R5

if you go 18650 or dual Cr123 - XM-L T6 (neutral color would be awesome)

and as far as multimode, MAKE IT HAVE MEMORY! the last one is so annoying to click through uber low, low and med just to get to HIGH!

since this is the BLF, we should be making the CPF guys cry.

maybe a triple XM-L flashlight for under 40 bux?

that would be mint :-D

esp if it could accept 18650 OR C/D size cells lol

even better, 5x XM-L :-D

Another vote to keep the 5x XM-L model alive. Good call xP.1337. That is until someone suggests 7 or 10 at which point I'll need to jump on that bandwagon. LOL

lol thats just overkill,no battery will sustain that draw lol

Damn xP, got my hopes up then shot it down. If one XM-L uses two 18650s, then it's possible with 10 batteries. What's wrong with that?

lol just go with my semi-DIY on the HID spot light from big lots

Another vote for XML

Unless it was coated in a metal film to reflect the light back inside the optic .. [ not let it out ] .. Now that would be a trick ! or treat !

What kind of a question is that ..feel free to come to me anytime for guidance my son ..Now go and buy a light .

QUOTE:

  1. Maximum reasonable price - 25USD
  2. LED type : XPG-R4 neutral or XM-L (prefered)
  3. Mode arrangement : Hi / Med (30%) / Lo (3%) or even better. ramping like the UF-h2 (very low low)
  4. Mode memory? : yes
  5. NiMH and 14500 support : both, with +1A on 14500 (high) and 2A on Nimh
  6. neutral
    very fast pwm!!!

I'd like the design and the Vaio tint of the Farka E09

I like the EO15 as well..

I agree with the above comments ^ 3 mode with 3 lumens /35/150 is perfect ..most lows ,, not bathroom crawling low enough .. most mediums are too high and don't save battery or show enough change between med and high.. the law of inverse square says you have to multiply times x4 to actually think you see the light double in strength ..i have 2 lights already that have an extra stupid low for no reason in the sequence ..almost as much of a pain in the ass as a strobe ..ok not that bad .. but honestly both are failed attempts and BLF creations blf mr lite and eastward 4 mode . they serve absolutely no useful purpose ,instead they only annoy..I agree that a light that actually pisses off cpf members is a good thing .that may mean it's not a half hearted light but a stone cold killer ..a gathered rescource that stops the hearts of every forum out there and turns heads ..One that drives people here just to be a part of it ..One that manufacturers seek to copy .. cost be damned .. as long as it beats the compatition on multiple levels .@ under 40$ works for me .

I wonder why we need a vendor in the first place ..the subject of manafont came up and i wonder why a vendor is needed ..a manufacturer yeah .. a vendor ?? no ..Why ?

Is this in case the light is screwed up that it can be dumped on them ? .. Is it so there is no risk to anyone but them .. so they get the risk / reward ??.I'm just curious what the thinking is here ?

[quote= Boaz]

I wonder why we need a vendor in the first place ..the subject of manafont came up and i wonder why a vendor is needed ..a manufacturer yeah .. a vendor ?? no ..Why ?

Is this in case the light is screwed up that it can be dumped on them ? .. Is it so there is no risk to anyone but them .. so they get the risk / reward ??.I'm just curious what the thinking is here ?

[/quote]

While the above reasons may be true, I believe it has mostly to do with purchasing logistics: For example, the manufacturer will make the custom light, but only at a minimum quantity of 500 (just a guess). If the light cost $20 to create, then that means it will take $10,000 to get this project rolling. I'm not aware of too many people other than vendors willing to take risk.